*{
    margin: 0;
    padding: 0;
}
.wrap{
    min-width: 600px;
}

#header,#footer{
    height: 50px;
    width: 100%;
    background: grey;
}
#left,#right{
    width: 200px;
    height: 200px;
    background: lightskyblue;
}

#middle{
    background: rgb(253, 239, 46);
    width: 100%;
    height: 200px;
    float: left;
}
#content{
    overflow: hidden;
}
#left{
    float: left;
    margin-left: -100%;
}
#right{
    float: left;
    margin-left: -200px;
}
.middle-inner{
    margin: 0 200px;
}